Many images and graphics, however, come in a PNG format — most notably screenshots. Luckily, with the Preview program that comes with your Mac computer you can convert a PNG to a JPEG.

If you’re looking for lossless PNG compression in a simple utility, PNG Compressor for the Mac is a utility designed for quickly dragging a folder or group of images into the icon or onto the window ...

In the early days of personal computing, there were so many incompatible file formats that one of the first programs many PC users ... save PNG files as JPGs in a number of common Mac apps ...